Asp.net and oracle

You can use Oracle Triggers to automatically capture changes (INSERT, UPDATE, DELETE) on each table and log them into an audit table.

Here's a simple outline for setting up triggers on each table:

1. Create an Audit Table: This table will store the audit logs, including details like the action (INSERT/UPDATE/DELETE), old and new values, and a timestamp.

   Example:

   CREATE TABLE audit_log (
       action VARCHAR2(10),
       table_name VARCHAR2(100),
       old_values CLOB,
       new_values CLOB,
       action_timestamp DATE,
       user_id VARCHAR2(100)
   );
   

2. Create a Trigger for Each Table: Create triggers for each table that you want to monitor. The trigger will capture the old and new values for each operation.

   Example trigger for an UPDATE:

   CREATE OR REPLACE TRIGGER audit_trigger_update
   AFTER UPDATE ON your_table_name
   FOR EACH ROW
   BEGIN
       INSERT INTO audit_log (action, table_name, old_values, new_values, action_timestamp, user_id)
       VALUES (
           'UPDATE', 
           'your_table_name',
           'OLD: ' || :OLD.column1 || ', ' || :OLD.column2, 
           'NEW: ' || :NEW.column1 || ', ' || :NEW.column2, 
           SYSDATE,
           USER
       );
   END;
   

3. Repeat for INSERT and DELETE:

   • For INSERT, you capture the new values only.

   • For DELETE, you capture the old values.

4. Generalize with PL/SQL: If you need to apply this across multiple tables, you can write a more dynamic solution using PL/SQL to loop through all tables.

Note: You’ll want to handle performance considerations, as logging each CRUD operation on every table could impact performance. Also, be cautious about logging sensitive information.

Use triggers and store just the columns that change, you can use JSON payloads for each change.

This stores one row per change, with old/new snapshots. Using CLOB + IS JSON keeps it compatible across versions.

-- Sequence for IDs
CREATE SEQUENCE AUDIT_LOG_SEQ;

-- Central audit table
CREATE TABLE AUDIT_LOG (
  AUDIT_ID     NUMBER PRIMARY KEY,
  TABLE_NAME   VARCHAR2(128) NOT NULL,
  ACTION       VARCHAR2(10)  NOT NULL,  -- INSERT/UPDATE/DELETE
  PK_VALUE     VARCHAR2(4000),          -- store the primary key value(s)
  OLD_VALUES   CLOB CHECK (OLD_VALUES IS JSON),
  NEW_VALUES   CLOB CHECK (NEW_VALUES IS JSON),
  CHANGED_BY   VARCHAR2(128) NOT NULL,
  CHANGED_ON   TIMESTAMP(6)  DEFAULT SYSTIMESTAMP NOT NULL,
  CLIENT_IP    VARCHAR2(64),
  MODULE       VARCHAR2(64),
  TXID         VARCHAR2(128) -- transaction id
);